Portable vaporizer for plant material

ABSTRACT

A portable vaporizer for plant material has an inhalation tube having a distal end for insertion into a cigarette lighter receptacle of a vehicle. An electrical heating element within the inhalation tube is powered by the vehicle&#39;s electrical system when the inserted into the cigarette lighter receptacle. A plant material chamber on the proximal end of the inhalation tube has openings allowing air from the inhalation tube to be drawn through the inhalation tube, heated by the electrical heating element, and then drawn through an air-permeable pouch containing plant material held in the plant material chamber. A housing having a mouthpiece and baffles surrounds the plant material chamber to reduce the temperature of the heated air and vaporized plant material. The user inhales the mixture of heated air and vaporized plant material through the mouthpiece by drawing air through the inhalation tube, plant material chamber and housing.

RELATED APPLICATION

The present application is a continuation-in-part of the Applicants' co-pending U.S. patent application Ser. No. 12/129,845, entitled “Portable Vaporizer For Plant Material,” filed on May 30, 2008.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to the field of vaporizers for releasing essential active constituents, such as nicotine, by heating plant materials. More specifically, the present invention discloses a portable vaporizer for plant materials.

2. Statement of the Problem

Inhalation devices for smoking tobacco or vaporizing various medicaments (e.g., nicotine) from plant materials are known in the art. These devices typically include an electrical heating element for igniting the tobacco or medicament. The resulting smoke and/or vapor is then inhaled by the user.

For example, U.S. Pat. No. 7,293,565 (Griffin et al.) discloses an electrically-heated cigarette smoking system with a stand containing a rechargeable power supply. As shown in FIGS. 13-16 of Griffin et al., the stand can also include recharging electronics powered by an adapter that plugs into the cigarette lighter of a vehicle.

However, there remains a need for an easy to use, hand-held device that allows for the release of the essential active constituents of a plant substance through vaporization, using sufficient heat and air to release them without burning the substance and without creating the toxic byproducts of combustion. This not only reduces the health risk to the user but also to neighboring non-smokers by alleviating second-hand smoke. In addition, there remains a need for a portable vaporizer that can be plugged directly into a conventional vehicle cigarette lighter.

Solution to the Problem. The present invention allows for the inhalation of the active constituents of a plant material by vaporization, rather than combustion. It includes a housing configured and sized to fit in the user's hand during use. In addition, it can be plugged into a conventional automobile cigarette lighter to create a heated air stream that is drawn through the plant material to produce a substance vapor that can be inhaled by an individual. The present device is unique in that it can be plugged into a conventional vehicle cigarette lighter and is completely independent of any power source once the electrical heating element has reached temperature.

SUMMARY OF THE INVENTION

This invention provides a portable vaporizer for plant material having an inhalation tube with a distal end for insertion into a cigarette lighter receptacle of a vehicle. An electrical heating element within the inhalation tube is powered by the vehicle's electrical system when inserted into a cigarette lighter receptacle. A plant material chamber on the proximal end of the inhalation tube has openings allowing air from the inhalation tube to be drawn through the inhalation tube, heated by the electrical heating element, and then drawn through an air-permeable pouch containing plant material held in the plant material chamber. A housing having a mouthpiece and baffles surrounds the plant material chamber to reduce the temperature of the heated air and vaporized plant material. The user inhales the mixture of heated air and vaporized plant material through the mouthpiece by drawing air through the inhalation tube, plant material chamber and housing.

These and other advantages, features, and objects of the present invention will be more readily understood in view of the following detailed description and the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention can be more readily understood in conjunction with the accompanying drawings, in which:

FIG. 1 is a front perspective view of a portable vaporizer 5 embodying the present invention.

FIG. 2 is a rear perspective view of the vaporizer 5 corresponding to FIG. 1.

FIG. 3 is a perspective view of a vaporizer 5 with the lid 32 removed and plant material 35 being loaded into the plant material chamber within the housing.

FIG. 3 a is a perspective view of a vaporizer 5 with the lid 32 removed and a pouch 37 containing plant material 35 being loaded into the plant material chamber within the housing.

FIG. 4 is a perspective view of the vaporizer 5 inserted into the cigarette lighter socket 50 in the dashboard of a vehicle.

FIG. 5 is a side view of a user inhaling through the vaporizer 5.

FIG. 6 is a horizontal cross-sectional view of the vaporizer 5.

FIG. 7 is a vertical cross-sectional view of the vaporizer 5.

FIG. 8 is an exploded cross-sectional view of the inhalation tube and plant material chamber assembly.

FIG. 9 is a cross-sectional view of the distal end of the vaporizer 5 initially inserted in a cigarette lighter socket 50.

FIG. 10 is a cross-sectional view corresponding to FIG. 9 after the vaporizer 5 has been fully inserted in the cigarette lighter socket 50 to power the electrical heating element 20.

FIG. 11 is a cross-sectional view corresponding to FIGS. 9 and 10 after the electrical heating element 20 has been heated and the bimetallic leaf springs 54 have released the vaporizer 5 to pop out.

FIG. 12 is a cross-sectional view corresponding to FIGS. 9-11 showing subsequent removal of the vaporizer 5 from the cigarette lighter socket 50.

FIG. 13 is a cross-sectional view of an embodiment of a vaporizer with a heat transfer element 26 to carry heat from the electrical heating element 20 to the air stream in the inhalation tube 10.

FIG. 14 is a cross-sectional view orthogonal to FIG. 13.

DETAILED DESCRIPTION OF THE INVENTION

FIGS. 1 and 2 are front and rear perspective views of an embodiment of the present invention. This embodiment is shown in further detail in the cross-sectional views of the vaporizer 5 depicted in FIGS. 6 and 7. The major components of the vaporizer 5 include an inhalation tube 10, an electrical heating element 20, a housing 40, and a plant material chamber 30.

FIG. 8 is an exploded cross-sectional view of the inhalation tube 10 and plant material chamber 30 assembly. The distal end of the inhalation tube 10 is designed for insertion into the socket of a conventional cigarette lighter socket 50 of a vehicle. An electrical heating element 20 is located at the distal end of the inhalation tube 10. This heating element 20 is initially powered by vehicle's electrical system, and then used to heat air drawn through the inhalation tube 10 after the vaporizer 5 has been withdrawn from the cigarette lighter socket 50. For example, the electrical heating element 20 can be a modified cigarette heating coil. The temperature of a lighter heating element is initially about 800°-1200° C., cooling to a temperature greater than 450° C. within about 10 seconds. The dimensions and thermodynamic properties of the inhalation tube 10 can be selected to result in a selected air temperature entering the plant material chamber 30 to cause vaporization of the desired medicaments from the plant material 35. For example, a temperature of about 125°-150° C. is suitable to vaporize the active constituents of tobacco.

The inhalation tube 10 provides a pathway for a heated air stream from the electrical heating element 20 at the distal end of the inhalation tube 10 to the plant material chamber 30 on the proximal end of the inhalation tube 10. Air flows through the inhalation tube 10 into the plant material chamber 30 and is generally insulated by the inhalation tube 10 to maintain the temperature of the air flow entering the plant material chamber 30. The inhalation tube 10 is also the stress point between the housing 40 and the heating element 20 and will absorb the forces produced by engaging the vaporizer with the cigarette lighter receptacle 50. For example, the inhalation tube 10 can be constructed of a heat-resistant material, such as medically-safe ceramic. The embodiment of the inhalation tube 10 shown in the drawings is a straight tube. It should be understood that the inhalation 10 could have any desired shape or cross-section.

The assembly at the distal end of the inhalation tube 10 also includes a number of components to enable the vaporizer 5 to interface with a conventional cigarette lighter socket 50, as illustrated for example in FIGS. 4 and 8-12. Returning to FIG. 8, the distal end of the inhalation tube 10 can be secured to a conventional cigarette lighter barrel 24 housing the electrical heating element 20, to minimize manufacturing costs. The barrel 24 is typically constructed as a single extruded tube which will allow air to flow freely through the heating element 20 through the barrel 24 and into the inhalation tube 10, as will be described below. For example, the distal end of the inhalation tube 10 can be coupled to the barrel 24 by a tubular inhalation guard 13, which inserts into the open end of the barrel 24 and is secured by lugs and/or a friction fit. The inhalation guard 13 also fits over the distal end of the inhalation tube 10 and is secured by lugs 14 that are bent inward to engage ribs or threads on the exterior surface of the inhalation tube 10, as shown in FIGS. 9-12.

A cylindrical outer housing 15 surrounds the barrel 24 and inhalation 13. The diameter of the outer housing 15 is designed to allow the distal end of the inhalation tube 10, inhalation guard 13 and barrel 24 to freely slide as an assembly within the outer housing 15 along its central axis. A spring 18 surrounds the exterior of the barrel 24 within the outer housing 15. This spring 18 is compressed between a flange at the proximal (upper) end of the inhalation guard 13 and an annular shoulder 16 in the interior surface of the outer housing 15 as the inhalation tube assembly 10, 13 and 24 advances. The corresponding annular shoulder 16 on the exterior surface of the outer housing 15 also acts as a stop to limit the extent to which the vaporizer 5 can be inserted into a conventional cigarette lighter socket 50.

The distal (lower) portion of the barrel 24 forms an annular skirt 25 that extends radially outward and surrounds the electrical heating element 20, as shown in FIGS. 8-12. When the vaporizer 5 is fully inserted into a lighter socket 50, bimetallic leaf springs 54 in the socket 50 grip this skirt 25 to hold the vaporizer 5 in place, as shown in FIG. 10, while the electrical heating element heats. The spring 18 is compressed during this period and exerts a biasing force that is held in check by the bimetallic leaf springs 54. However, when the electrical heating coil 20 has heated the adjacent bimetallic leaf springs 54 to a predetermined temperature, the bimetallic leaf springs 54 deform outward sufficiently to release the skirt 25 of the barrel 24. The spring 18 then causes the vaporizer to partially eject from the cigarette lighter socket 50. In other words, the spring causes the lighter to “pop” out a short distance, as illustrated in FIG. 11. This breaks the electrical contact between the rivet 22 and the electrical contact 52 in the base of the socket 50. The vaporizer 5 can then be withdrawn from the cigarette lighter socket 50, as shown in FIG. 12.

It should be noted that other types of bimetallic springs or heat-sensitive mechanisms could be substituted for the leaf springs 54 For example, a bimetallic disk behind the electrical heating element 20 could be employed to pop-out the vaporizer 5.

A convection plate 12 is mounted above the neck of the barrel 24 to serve as the point of attachment for the heating coil 20 by a metal rivet 22. The convection plate 12 also has a pattern of holes that will allow air to pass from the electrical heating element 20 into the barrel 24 and through the inhalation tube 10. The pattern and size of holes help to determine the amount of air flow and the temperature of the air stream through the inhalation tube 10.

The electrical heating element 20 can be constructed as a flat coil of nickel-chrome wire. For example, the electrical heating element 20 can be made of a corrosion-resistant wire made of 80% nickel and 20% chromium with a melting point of about 1400° C. Ni-chrome wire can be wound into a thin coil to a predetermined electrical resistance and when current from the vehicle's electrical system (typically about 15-20 amps) is passed through the heating element 20, it produces heat. The center of the electrical heating element 20 is attached to the metal rivet 22 and the periphery of the heating element 20 is attached to the skirt 25 at the distal end of the barrel. The rivet 22 and barrel 24 serve as the electrical contacts to establish a complete circuit between the vehicle's electrical system (i.e., battery) and the electrical heating element 20. In particular, an electrical contact 52 in the base of the socket 50 makes contact with the rivet 22 when the distal end of the vaporizer 5 is fully inserted into a cigarette lighter socket 50, as shown in FIG. 10. The other electrical contact for powering the heating coil 20 made through the metal barrel 24, which is in contact with the metal wall of the socket 50 that is grounded to the vehicle.

An O-ring seal 19 between the convection plate 12 and inhalation tube 10 can be used to form an air-tight seal between the electrical heating coil 20 and the inhalation tube 10. When the inhalation tube 10 is secured in the inhalation guard it is pressed onto the inhalation seal 19 which forms an air seal forcing the air stream to flow through the electrical heating coil 20 and into the inhalation tube 10 without ambient-temperature air leaking into the air stream. The inhalation seal 19 can be made from a heat-resistant, medicinally-safe, yet pliable material, such as silicone.

The plant material chamber 30 is attached at the proximal end of the inhalation tube 10 and is typically enclosed within the housing 40. In particular, the proximal end of the inhalation tube 10 is fitted into one side or the bottom of the plant material chamber 30 and sealed with a gasket. This gasket forms a seal between the plant material chamber 30 and the inhalation tube 10 and completes the air tight seal from the heating coil 20 to the plant material chamber 30. The plant material chamber 30 can perforated by elongated vents or openings 34 about its outer surface. These vents 34 provide non-restricted air flow from the inhalation tube 10 through of the plant material chamber 30 into the interior of the housing 40. The plant material chamber 30 can be generally cup-shaped with an opening extending through the wall of the housing 40 to accept a removable, air-permeable material holder 31 containing a quantity of plant material 35 for vaporization, as shown in FIG. 3. During use of the vaporizer 5, the open end of the plant material chamber 30 is sealed by a cover or lid 32 to maintain air flow through the inhalation tube 10 and electrical heating element 20. The heated air stream flows from the heating coil 20 through the inhalation tube 10 and into the plant material chamber 30 where vaporization of the plant material 35 occurs. This vapor stream is drawn through the openings 34 in the plant material chamber 30 into the interior of housing 40, and exits the housing 40 through the mouthpiece 44 at the proximal end of the housing 40 as the user inhales. The inhalation tube 10, plant material chamber 30, seals, lid 32, and baffles 42 can be made of heat-resistant, medicinally-safe materials, such as ceramic, to provide thermal insulation. Charcoal can be placed into the inhalation tube 10 to help alleviate any unwanted taste from the heating element 20. Optionally, the plant material chamber 30 can also include a filter to help contain the plant material 15 and filter the vapor stream

The housing 40 can have an egg-shaped or ovoid cross-section, for example. The interior of the housing 40 can include a number of baffles 42 to create a more circuitous route for air flow from the plant material chamber 30 to the mouthpiece 44 and provide additional cooling and mixing of the vapor stream. The distal end of the housing 40 can be flared radially outward adjacent to the proximal end of the outer lighter housing 15 to provide a tactile device to help prevent the user from sliding fingers over the heating assembly. The housing 40 can either be made of heat-resistant, medicinally-safe materials, such as ceramic, to provide thermal insulation, or it can made of a suitable polymer capable of withstanding the temperatures involved.

To use the vaporizer 5, the user initially places a quantity of plant material 35 into the plant material chamber 30 of the vaporizer 5. For example, this can be done by removing the cap 32 covering the external opening to the plant material chamber 30 and then inserting an appropriate amount of the plant material 35 into the material holder 31, which is placed into the plant material chamber 30 as depicted in FIG. 3. The lid 32 is then replaced to close the external opening of the plant material chamber 30 and retain the material holder 31 and plant material 35 within the plant material chamber 30, as shown for example in FIG. 7

FIG. 3 a shows another embodiment of the present invention in which the plant material 35 is held within a pouch or pod 37 made of a suitable high-temperature material, such as air-permeable mesh. The pouch 37 is placed within the plant material chamber 30 of the vaporizer 5, and the lid 32 is then replaced to close the plant material chamber 30. The pod 37 can be a casing formed around a quantity of plant material that allows air to pass freely through the pouch material as well as the plant material. The plant material should be loosely packed so that air can freely circulate through it. The pod 37 should be capable of withstanding heated air up to about 365° F., but will generally be used at about 250° F. in addition, the pouch material should be medicinally safe throughout its range of operating temperatures. For example, the pod 37 can be made of plastic mesh, such as nylon screening cloth, which is commercially available as a mesh. This material can be sterilized and is safe up to 437° F. It is also certified by the FDA. The pod 37 can be manufactured using thermal vacuum molding to form the body of the pod 37, followed by ultrasonic welding to seal the plant material within the pod 37.

Next, the user inserts the distal end of the inhalation tube into the cigarette lighter receptacle 50 of a vehicle to connect the electrical heating element 20 to the electrical system of the vehicle. This is shown in the perspective view provided in FIG. 4. FIG. 9 is a cross-sectional view of the distal end of the vaporizer 5 initially inserted in a cigarette lighter socket 50. FIG. 10 shows the vaporizer fully inserted to heat the electrical heating element 20. FIG. 11 is a cross-sectional view after the electrical heating element 20 has been heated and the bimetallic leaf springs 54 have released the vaporizer 5 to pop out. The user then withdraws the vaporizer 5 from the cigarette light receptacle 50 as shown in FIG. 12.

The user inhales through the mouthpiece 44 as shown in FIG. 5, thereby creating negative pressure to draw air through the inhalation tube 10 where it is heated by the heated element 20 and then drawn through the plant material chamber 30 to produce a mixture of heated air and vaporized plant material. In the embodiment shown in FIG. 3 a, the heated air is drawn through both the plant material chamber 30 and the air-permeable pouch 37 contained within to produce a mixture of heated air and vaporized plant material. This mixture of heated air and vaporized plant material is drawn out of the plant chamber 30 through its openings 34 into the interior of the housing 40. The vapor stream is directed by the baffles 42 within the housing 40 and exits via the mouthpiece 44.

FIGS. 13-14 show two orthogonal cross-sectional views of an embodiment of the present invention that includes a heat transfer element 26 to transfer heat from the heating coil 20 to the airstream in the inhalation tube 10. The heat transfer element 26 is in thermal contact with the heating coil 20 and conducts heat axially within the inhalation tube. This configuration can also include a number of air intake openings 11 extending through the wall of the inhalation tube 10 at a distance above the heating coil 20. Air entering through these openings 11 will be heated by the heat transfer element 26 before entering the plant material chamber 30. If desired, air flow through the heating coil 20 can be blocked by a ceramic spacer 27 to provide a more moderate and uniform air temperature entering the plant material chamber 30. This spacer 27 replaces the perforated convection plate 12 shown in the previous embodiment. Blocking air flow through the heating coil 20 might also help to reduce any unpleasant taste or smell associated with the heating coil 20.

The heat transfer element 26 can have any desired configuration and be made of any material having suitable thermal conductivity. For example, the heat transfer element 26 can be made of thermal pyrolytic graphite (TPG) available from Momentive Performance Materials, Inc. of Strongsville, Ohio. This material is made by chemical vapor deposition of cracked methane, followed by a combination of pressure and thermal treatment at very high temperatures, to produce a material with an in-plane thermal conductivity of more than 1500 W/m deg. K. In contrast, copper has a thermal conductivity of about 400 W/m deg. K. TPG is somewhat fragile and is usually supplied embedded in an aluminum plate.

The above disclosure sets forth a number of embodiments of the present invention described in detail with respect to the accompanying drawings. Those skilled in this art will appreciate that various changes, modifications, other structural arrangements, and other embodiments could be practiced under the teachings of the present invention without departing from the scope of this invention as set forth in the following claims. 

1. A portable vaporizer for plant material comprising: a distal end for insertion into a cigarette lighter receptacle of a vehicle; an electrical heating element powered by the electrical system of the vehicle when the distal end of the vaporizer is inserted into a cigarette lighter receptacle; an air-permeable pouch containing plant material; a plant material chamber for holding the pouch and having openings allowing heated air from electrical heating element to be drawn through the pouch and plant material; and a housing having a mouthpiece for drawing air through the plant material chamber and pouch to produce a mixture of heated air and vaporized plant material.
 2. The vaporizer of claim 1 wherein the pouch is comprised of a plastic mesh.
 3. The vaporizer of claim 1 wherein the plant material chamber is within the housing and further comprises an external opening extending through the housing to receive the pouch, with a removable cap covering the opening of the plant material chamber.
 4. The vaporizer of claim 1 wherein the housing further comprises baffles between the plant material chamber and mouthpiece.
 5. A portable vaporizer for plant material comprising: an inhalation tube having a distal end for insertion into a cigarette lighter receptacle of a vehicle; an electrical heating element within the inhalation tube powered by the electrical system of the vehicle when the inhalation tube is inserted into a cigarette lighter receptacle, said inhalation tube enabling air to be drawn through the inhalation tube and heated by the electrical heating element; an air-permeable pouch containing plant material; a plant material chamber for holding the pouch and having openings allowing heated air from the inhalation tube to be drawn through the plant material in the pouch; and a housing having a mouthpiece for drawing air through the inhalation tube, plant material chamber and pouch to produce a mixture of heated air and vaporized plant material.
 6. The vaporizer of claim 5 wherein the housing further comprises baffles between the plant material chamber and mouthpiece.
 7. The vaporizer of claim 5 further comprising a heat transfer element in the inhalation tube transferring heat from the electrical heating element to air in the inhalation tube.
 8. The vaporizer of claim 5 wherein the electrical heating element is within the distal end of the inhalation tube to make electrical connection with electrical contacts in a cigarette lighter receptacle when the inhalation tube is inserted into a cigarette lighter receptacle.
 9. The vaporizer of claim 5 further comprising an outer housing surrounding the distal end of the inhalation tube, and a spring between the outer housing and inhalation tube to partially eject the vaporizer from a cigarette lighter receptacle when the electrical heating element reaches a predetermined temperature.
 10. The vaporizer of claim 5 wherein the plant material chamber is within the housing and attached to the proximal end of the inhalation tube.
 11. The vaporizer of claim 10 wherein the plant material chamber has an external opening extending through the housing to receive plant material, and further comprising a removable cap covering the opening of the plant material chamber.
 12. A portable vaporizer for plant material comprising: an inhalation tube having a proximal end and a distal end for insertion into a cigarette lighter receptacle of a vehicle; an electrical heating element within the distal end of the inhalation tube powered by the electrical system of the vehicle when the inhalation tube is inserted into a cigarette lighter receptacle; a housing having an interior and a mouthpiece; an air-permeable pouch containing plant material; and a plant material chamber for holding the pouch on the proximal end of the inhalation tube and enclosed within the housing, said plant material chamber having at least one opening into the interior of the housing; wherein negative pressure at the mouthpiece of the housing draws air through the inhalation tube where the air is heated by the heated element and then drawn through the plant material chamber and pouch to produce a mixture of heated air and vaporized plant material.
 13. The vaporizer of claim 12 further comprising baffles between the plant material chamber and the mouthpiece.
 14. The vaporizer of claim 12 further comprising a heat transfer element in the inhalation tube transferring heat from the electrical heating element to air in the inhalation tube.
 15. The vaporizer of claim 12 wherein the electrical heating element is within the distal end of the inhalation tube to make electrical connection with electrical contacts in a cigarette lighter receptacle when the inhalation tube is inserted into a cigarette lighter receptacle.
 16. The vaporizer of claim 12 further comprising an outer housing surrounding the distal end of the inhalation tube, and a spring between the outer housing and inhalation tube to partially eject the vaporizer from a cigarette lighter receptacle when the electrical heating element reaches a predetermined temperature.
 17. The vaporizer of claim 12 wherein the plant material chamber has an external opening extending through the housing to receive plant material, and further comprising a removable cap covering the opening of the plant material chamber. 